The party growers were having a good time while everyone else outside was sick.
While they were dancing and having a good time the clock rang and everyone became still and it grew scilent.
After the people were done dancing they went to their rooms to settle down.
Now that the castle was quiet and they clock started ringing every half hour instead of every hour the people in the castle stated to wondering why it was doing that. They soon realized that Prospero was behind all of this...
Prospero called everyone in for a meeting in the seventh room and soon they realized it wasn't a good idea.
Turns out that Prince Prospero was the one poisoning all the people and that he wanted to kill everyone so he was the "red death" after all.